Loose neutral

[Cocat2517]

Hi
Had an issue with a socket last night. It briefly made a weird fuzzing sound before tripping the switch.

I shut off power and opened it up, the neutral was loose in the terminal, which explains what happened (intermittent connection causing arcing & tripping switch?). What I don't understand is how the neutral became loose in the first place. What would cause that? Socket has been in place for about 10 years and was a replacement for the old original socket.

One possible explanation was the presence of green goo. I understand this is plasticiser seeping from the insulation sleeving & reacting with the copper. The house was built in 1968 so obviously has some of that crappy wiring in it still. There was green goo inside the terminals and on the wiring itself. Could this have caused the neutral to come loose?

I understand this goo isn't dangerous, so I've cleaned it off, cleaned out the terminals & reconnected the socket. All working ok.

 

[EFLImpudence]

Caused by slightly loose in the first place which causes heating, the wire becomes softer, is pushed away from the tightest part thus making it even looser and hotter next time.

You are showing the red (presumably live) wire yet the neutral terminal looks like the damaged one.
Are we to take it that the socket was wired (apparently) the wrong way round?

Of course, if the red wire actually is the neutral, then some more investigation looks necessary.


I wouldn't think the goo has anywthing to do with this.

 

[phatboy]

Replace the socket, it's been damaged and so poses a risk again.

 

[Cocat2517]

Thanks for replies. Definitely wired correctly, i.e. black neutral wire in neutral terminal, red in live terminal. I wasn't showing any particular wire in that photo, just the wiring in general, live is just more in focus than the rest.

Is the socket definitely damaged? I saw no sign of damage to either wire or socket terminal , just the green gunk in it which may be giving the appearance of damage. Would the loose connection/arcing have caused damage that's not visible?

Will replace socket regardless, not worth the risk.

 

[phatboy]

Thanks for replies. Definitely wired correctly, i.e. black neutral wire in neutral terminal, red in live terminal. I wasn't showing any particular wire in that photo, just the wiring in general, live is just more in focus than the rest.

Is the socket definitely damaged? I saw no sign of damage to either wire or socket terminal , just the green gunk in it which may be giving the appearance of damage. Would the loose connection/arcing have caused damage that's not visible?

Will replace socket regardless, not worth the risk.

If you cannot see damage there probably isn't, but for the cost I'd do it.

Also, that backbox is missing it's rubber grommet, and there is no sleeving on the earth. Easily fixed in both cases... but you may want to inspect more sockets and switches!

 

[Cocat2517]

Yeah, as I say will be replacing it regardless. Noticed the earth sleeving (or lack of) so will be doing that too. Rubber grommet presumably goes where the cable enters the back box? I'll pick some up. Thanks.

I'd not heard of the green goo issue before this, but now I know about it and the fact it's possibly affecting other sockets I'll be inspecting all of them and cleaning/rectifying any issues. Anything found that's not straightforward I'll get someone in.

 

[Cocat2517]

Just to confuse things....

Before I replace this socket, we were considering getting another socket added. This one I believe (will confirm before doing anything) is a spur from the ring main. I understand you can only spur once off a ring socket and you can't spur off a spur. There aren't really any other nearby sockets to spur from either.

I was however reading about how you can (allegedly) spur off into an fcu, after which you can add more spurs/sockets as a radial. So, I'd replace this socket with a 13a fcu, then run (2.5?) cable to a socket, then 2.5 to another socket. It'd restrict the load on both sockets to 13a/3kw, but we don't exceed that as it is. Is this allowed?

 

[EFLImpudence]

Yes, that's right.

 

[winston1]

I understand you can only spur once off a ring socket and you can't spur off a spur.

You can have more than one spur off a socket (if you can get the wires in) but you cannot spur off a spur.

 

[Cocat2517]

You can have more than one spur off a socket (if you can get the wires in) but you cannot spur off a spur.

Oh ok, I thought the rule was only one spur off a ring main socket.

 

[AndyPRK]

The cables been leaking the green liquid.
Clean it off with alcohol.

 

[Cocat2517]

The cables been leaking the green liquid.
Clean it off with alcohol.

Yep, got some isopropyl spray I was going to use.

Perhaps cut off the sleeving on that section and replace with some heat shrink??

 

[conny]

Oh ok, I thought the rule was only one spur off a ring main socket.

It is. No more than one spur off a socket and no more spurs than sockets.
However, as has been said, you can change your existing socket to a FCU fused at no more than 13A and run a series of spurs from that. Bear in mind the total load for those spurs cannot exceed 13A

 

[Cocat2517]

It is. No more than one spur off a socket and no more spurs than sockets.
However, as has been said, you can change your existing socket to a FCU fused at no more than 13A and run a series of spurs from that. Bear in mind the total load for those spurs cannot exceed 13A

Yep, that's the plan, thanks.

Regarding this green goo, does it affect the entire length of cable? Or just the section when it attaches to terminals?

 

[DetlefSchmitz]

It is. No more than one spur off a socket and no more spurs than sockets.

Conny, I think this is a remembered notion from some old guidance. I don't believe there is any longer any such regulation.